title: Coupling of HRT II and AS-OCT to evaluate corneal endothelial cell loss and in vivo visualization of the Ahmed glaucoma valve implant.
abstract: OBJECTIVE
  To report corneal endothelial cell loss and in vivo visualization of the Ahmed glaucoma valve implant in eyes with refractory glaucoma.
  
  
  METHODS
  Ten eyes underwent Ahmed valve implant surgery and were followed-up for 12 months. Data collected included intraocular pressure (IOP), number of antiglaucoma medications and surgery-related complications. At 6 and 12 months postoperatively, the intracameral length of the drainage tube (ICL) and the distance between the tube and the cornea (T-C distance), and the iris (T-I distance) were assessed using anterior segment optical coherence tomography (AS-OCT). Heidelberg cornea tomograph II (HRT II) was used to measure the corneal endothelial cell density.
  
  
  RESULTS
  Mean (+/-SEM) preoperative IOP was 29.5+/-4 mmHg. Mean postoperative IOP was 11.6+/-2 at 12 months (P<0.01). Over a 6-month period, mean corneal endothelial loss was 7.9%+/-2.5 in the central and 7.5%+/-2.4 in the peripheral cornea (P<0.01). There was no correlation between central or peripheral corneal endothelial cell loss and the T-C, T-I distance or the ICL of the tube.
  
  
  CONCLUSIONS
  Corneal endothelial cell loss occurs following Ahmed valve implant surgery, this appears to be multifactorial. AS-OCT and HRT II are promising methods for the follow-up of patients with a glaucoma drainage device.
authors.affiliation: Department of Ophthalmology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: E
authors.initials: E
authors.lastname: Mendrinos
authors.forename: A
authors.initials: A
authors.lastname: Dosso
authors.forename: J
authors.initials: J
authors.lastname: Sommerhalder
authors.forename: T
authors.initials: T
authors.lastname: Shaarawy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D055954:Corneal Endothelial Cell Loss / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D041623:Tomography, Optical Coherence / Q000379:methods*; D055815:Young Adult
chemical_list: D000959:Antihypertensive Agents